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Copper-silver alloys have widely applied in many different areas such as information and communication technology, rail transportation, power transmission lines, microelectronics, machinery manufacturing, chemical processing industries, coinage, ornamental parts, etc [1, 2]. A group of ternary Ag-Cu alloys with different elements is used for binding different materials (brazing, fillers, and pastes). For example, Ag-Cu-Pd alloys are used in dentistry, as amalgams improvers or joint fillers for different dental materials [3]. Ternary AgCuIn alloy uses as a bonding metal layer; the use of AgCuIn as the bonding metal, greatly reduces the manufacturing costs of LED chip and helps to improve the life of the LED chip. Copper and its alloys belong to the group of semi-noble metals however they are not highly resistant to corrosion in some of the environments [4, 5]. Corrosion has particularly attracted attention due to the significant impact on the performance and reliability of this industrially important material group in their applications, as well as on the economy. Standard methods for characterization of corrosion films are: X-ray diffraction (XRD), Raman spectroscopy and scanning electron microscopy (SEM) with Energy Dispersive Spectroscopy (EDS) [6, 7]. The positive mode laser desorption ionization (LDI) mass spectrometry method can be successfully applied to analyze the composition of the corrosion film. In our previous work, it has been shown that the amount of sample required for the LDI method is much smaller than the sample quantity required for the methods mentioned above [8]. The purpose of this work was to study the possibilities of direct analysis of the corrosion films formed on Ag60Cu26Zn14, Ag58.5Cu31.5Pd10, and Ag63Cu27In10 alloys using the negative mode laser desorption ionization (LDI) mass spectrometry method. The corrosion films of Ag60Cu26Zn14, Ag58.5Cu31.5Pd10, and Ag63Cu27In10 alloys were obtained after anodic potentiostatic polarization treatme

This study has developed an improved and fast microwave-assisted procedure for extraction of high yields of natural antioxidants from artichoke leaves dust. The material is derived as an abundant residue remained after processing for the industrial tea blends preparation, having no commercial value. A key factors for optimization of the total polyphenolic (TPC) and flavonoid content (TFC) and antioxidant activities have been determined by using single factor experiments along with a response surface methodology. The optimal conditions for maximizing the combination of TPC/TFC and antioxidant activity were obtained as follows: ethanol concentration 67.81%, extraction time 50 s, liquid/solid ratio 41.78 mL/g, microwave power 180 W, whereas the corresponding responses resulted in: TPC − 205.59 ± 7.30 mg GAE/g dw, TFC − 79.75 ± 1.12 mg QE/g dw, and FRAP −1008.14 ± 37.15 mmolFe2+/g dw. Only 14.7 µg/mL of the extract concentration is required to inhibit 50% of DPPH free radicals. A comparative study confirmed that the proposed procedure yielded higher TPC, TFC and antioxidant activities than available extraction methods. It highlights a several fold reduced extraction time, caring an eco-friendly principle for obtaining of antioxidants from industrial, medicinal crop residues, which would be further easily valorized in food and pharmaceutical industry.

Based on the analogy between manufacturing and mining (i.e. ore 'production'), smart mining has four dimensions: (i) advanced digital-oriented technologies (such as Cloud computing and the Internet of things) with automated Cyber-Physical Systems (CPSs), adaptable production processes (dependent on working conditions) and production volume control (with optimal resource consumption); (ii) smart maintenance of CPSs; (iii) new ways for workers to perform their activities, using advanced digital-oriented technologies; and (iv) smart supply-chain (procurement of materials and spare parts / products delivery). This paper presents a case study on the smart mining approach implemented at a coal mining system in Serbia.

In the complex ecosystem of gut microbiota, lactic acid bacteria (LAB)+B represent prevalent, abundant, and highly important subpopulation. LAB+B are well-known for their health-promoting effects: they are found to positively influence gut microbiota diversity, modulate immune response and intestinal permeability, and produce bioactive or regulatory metabolites. Bifidobacteriaceae represent critical early colonizers of the human gut, and the depletion of this microbial group in infants is correlated with allergy development. LAB+B are considered as one of the first human gut colonizers and recent studies have shown that humans might be exposed to them even in the womb. The primary role of the human gut microbiota, as in other animals, is its contribution to digestion. Several types of health-promoting dietary polyphenols are able to boost the abundance of LAB+B in human trials, but also in in vitro tests and animal models. A molecular methods-based insight into gut microbiota diversity showed presence of its disturbed composition-dysbiosis-in various diseases.

Five samples of feces from premature born nursling were taken from Institute of Neonatology (Belgrade). Three different media based on MRS was used for isolation of intestinal isolates of lactic acid bacteria. From 25 obtained cultures nine were selected for further investigation on potential probiotic ability and compared with Lactobacillus rhamnosus GG as reference strain. Preliminary identification has been performed according morphological traits (Gram staining, cells shape and colony characteristics on agar plate). Isolates suspected to lactobacilli and bifidobacteria were tested for selected physiological and biochemical characteristics. Tests for investigation of potential probiotic ability comprised antimicrobial activity against wide range of pathogens, sensitivity to simulated gastrointestinal tract conditions, and antibiotic resistance. The morphological and physiological profiles showed that all strains are Lactobacillus rhamnosus. There were some differences in their sugar fermentation pattern as well as in their antimicrobial activities. All strain grown well in simulated gastrointestinal condition but their sensitivity was greater on bile acids and pancreatin compared with low pH (1, 2 and 3) and pepsin. Most isolates showed good probiotic potential with similar properties with referent strain Lactobacillus rhamnosus GG determined in vitro.

The paper presents how the concept and technology of Open Badges are applied in the GRASS project for acknowledging, grading, awarding and recognizing learners' efforts and achievements in developing their soft skills (like self-regulation, leadership, collaboration, skilled communication, problem solving and innovation). Specifically, the paper describes a 4-phase model, called SAGRADA that was developed to support the process of awarding badges in the context of the GRASS project. The core of the SAGRADA model is a set of metrics, carefully developed for specific practical application cases following well-known pedagogical approaches. The metrics enable measuring and tracking learners' efforts in developing their soft skills. The paper also presents a specific application case based on the SAGRADA model, including the preliminary results of the first observational study, and plans for applying learning analytics methods and techniques in further activities of the GRASS project.

Copper nanoparticles (CuNPs), with an average particle size of about 5 nm, was prepared by the simple chemical reduction procedure. TEM and UV– Vis spectroscopy contributed to the analysis of size and optical properties of CuNPs, and their antibacterial activity was evaluated toward human pathogenic bacteria Escherichia coli and Staphylococcus aureus, in a concentration dependent manner. The changes in the cell membrane morphology of tested strains were investigated by atomic force microscope (AFM), after 2 h of their contact with CuNPs. It was found that CuNPs cause different types of cell membrane disruptions, as well as that S. aureus bacteria were slightly resistant to the cell membrane damage than E. coli.

This paper presents a modern systematic approach to the improvement of the management system for auxiliary mechanization operations at an open-pit coal mine. The approach is based on an integrated model (IM) of business processes and information systems (IS). Within IS/ICT system development, implementation of GPS/GPRS technologies is also described in this paper. Experimental research on this holistic approach was performed at the thermal power plants and open-pit coal mines in Kostolac, Serbia. Results confirmed the importance of this concept for auxiliary mechanization operations management based on selected KPIs (e.g. working moto-hours of the machine) and technical parameters (e.g. readiness).

The aim of this work was to investigate the process of electrodeposition of silver powder from nitrate electrolyte for usage in electronic. It was performed a series of experiments to test the solubility of silver powder in nitric acid and the effect of Cu+, Pb2+ and Cr2+ ions on the properties of the silver powder. The morphology of silver powder obtained from nitrate electrolyte, was studied using the scanning electron microscope (SEM model: JOEL JSM-6610LV). Chemical composition of the silver powder was determined using the Energy Dispersive X-ray Spectroscopy (EDS). The EDS spectra for silver powder were recorded using the X-ray spectrometer, attached to the scanning electron microscope.

In the present study, we investigated the use of spray drying as a way to prepare dairybased powders with high number of viable cells of the potential probiotic strain L. plantarum JS7A. Microencapsulation was done using reconstituted skim milk (RSM), inulin and maltodextrin as carriers. When RSM was used as a spray drying carrier a microbial survival rate of 73 % was achieved, although the partial substitution of skim milk with inulin also resulted in high level of survival of 70 %. The poorest survival of 41 % was obtained with maltodextrin as a carrier. The moisture contents in powders were ranging from 4.1 % to 4.4 %. Spray drying process stressed the cells which was shown by increased sensitivity to NaCl. However, it was obtained that reconstituted skim milk showed the significantly lower inhibition of cells of 49 % comparing with inulin and maltodextrin with 55 and 75 % of inhibition, respectively.

The paper discusses the antimicrobial bioactive band-aids, a modem means of wound management and healing, which are effective against a wide spectrum of microorganisms. Ion-exchange fibres and nonwoven textile materials composed of PP/viscose blend were used as a textile basis. Antimicrobial bioactive band-aids were manufactured in two routs:. -by chemisorption of gentamicin sulfate by ion-exchange fibres; and-by adhesion of gentamicin sulfate on nonwoven material with the aid of a polymer carrier (chitosan).For assessment of antimicrobial activity, the diffusion method on an agar medium has been used. Staphylococcus aureus, Pseudomonas aeruginosa, Klebsiella, Escherichia coli and Candida albicans have been utilised. The kinetics of active substance desorption has been examined through dissolving rate of medical substance from transdermal band-aid in vitro.Physical-chemical foundations and kinetics of desorption of gentamicin sulfate in vitro are described by a mathematical model which can be used for prognosis of prolonged release of medical substance from band-aid as a transdermal system.

Poster presented at the 12th Annual Conference of the Materials Research Society of Serbia - YUCOMAT 2010, Herceg Novi, Montenegro, September 6–10, 2010

Giardia infection is an ongoing problem in Serbia, since 8.0% of the children in the Belgrade area are infected. In the light of the zoonotic potential of Giardia infection, a total of 248 companion animals (167 dogs and 81 cats) were examined for giardiasis in the same urban area. The overall rates of infection in dogs and cats were 14.4% (24/167) and 22.2 % (18/81), respectively. Significantly (p lt 0.05, p lt 0.01) higher infection rates were found in stray (18.7%) and farm (36.4%.) dogs than in household pets (7.4%.). Furthermore, the rate of infection was significantly (p lt 0.01) higher in domestic cats than in household dogs (22.2% vs. 7.4%). The owners and all 16 of their family members of five out of the six household pet dogs excreting Giardia were Giardia-negative, while both the owner of one dog and the only other family member were Giardia-positive. The data demonstrate that potential animal reservoirs (dogs and cats) exist in urban Serbia and underline the possibility of transmission between dog and man in close contact, thus having important implications for the epidemiology of giardiasis in urban areas.